This invention relates to stabilized aqueous antimicrobial compositions which comprise a halogenated amide as the active (i.e., antimicrobial) ingredient and to processes for their preparation.
Halogenated amides such as 2,2-dibromonitrilopropionamide are useful as antimicrobials in various applications. See, for example, Nolan et al., U.S. Pat. No. 2,419,888; Schmidt et al., U.S. Pat. No. 3,493,658; and CIBA S.A. Belgian Patent No. 668,336. Certain halogenated amides are useful in the finishing of textiles, as taught by Chance et al., U.S. Pat. Nos. 3,350,164 and 3,403,174. Others are useful as slimicides in aqueous systems such as paper pulp and cooling towers and as sterilizing agents for drycleaning fluids. See, for example, Wolf, U.S. Pat. No. 3,647,610; Wolf, U.S. Pat. No. 3,649,166; Wolf et al., "2,2-Dibromo-3-Nitrilopropionamide, A Compound with Slimicidal Activity", Applied Microbiology, Vol. 24, No. 4, pp. 581-584 (1972); and Moyle et al., U.S. Pat. No. 3,928,575.
In the storage, shipment and use of such antimicrobial agents, it is often desirable to employ the antimicrobial agent in the form of a liquid concentrate composition wherein the halogenated amide antimicrobial is dissolved in a mixture of an organic solvent and water. However, the presence of water in such compositions often accelerate decomposition of the halogenated amide antimicrobial. See, for example, U.S. Pat. No. 3,689,660 and "Rates and Products of Decomposition of 2,2-Dibromo-3-Nitrilopropionamide", Exner et al., J. Agr. Food Chem., Vol. 21, No. 5, pp. 838-842 (1973). Accordingly, in order to obtain adequate stability for many purposes, it has heretofore been necessary to resort to essentially anhydrous liquid concentrate compositions and it has therefore been necessary to essentially exclude water from the ingredients used in the preparation thereof.
Consequently, it is desirable to provide a means of reducing the adverse impact of water upon the aforementioned liquid concentrate compositions and to thereby provide (a) aqueous halogenated amide antimicrobial compositions having improved stability and (b) simplified, economical processes for the preparation of stable liquid concentrate compositions.